The present invention relates to an improved microtip probe, and a method of manufacture for microscopy uses such as scanning probe microscopy ("SPM"). More particularly, the present invention addresses a need to provide microtip probes with operating properties and shapes complimenting the probe's intended use. Further the present invention extends a probe's life by improving the probe's wear resistance, e.g., erosion resistance.
Microscopy probes desirably consist of a microtip shaped for a particular application. U.S. Pat. No. 5,546,375 to Shimada, et al., discloses a method of manufacturing a cantilevered noble metal microtip for a scanning tunneling microscope. While the Shimada noble metal microtip achieves surface observation at an atomic or molecular-scale resolution, noble metals are not highly wear resistant. U.S. Pat. No. 5,386,110 to Toda, discloses a method of making a cantilever chip for a SPM probe having an undoped silicon microtip. Toda relies on the selective use of different microtip shapes in order to measure samples having various shapes.
Prior art manufacturing methods also include the deposition of a gold or cobalt/chromium layer on shaped silicon microtips or the use of doped diamond microtips. The prior art metal coating suffers from low reliability due to microtip wear, especially in applications requiring the microtip to contact the probed surface. Doped diamond microtips may present an excessively hard tip for some applications and also suffer from having a high resistivity and therefore are not suitable for high frequency electrical response applications.
The present invention provides an improvement over the prior art by enhancing and tailoring probe operating properties and extending probe life through the use of a shaped microtip with a novel multilayer microtip treatment.
Accordingly, it is an object of the present invention to provide a novel method of manufacturing a multilayer probe microtip having selectable operating properties during manufacture and enhanced wear resistance during use.
It is another object of the present invention to provide a novel method of overlying a microtip with a layer to obtain selected microtip operating properties and subsequently applying a protective layer resistive to wear without adversely affecting said microtip shape and operation.
It is yet another object of the present invention to provide a novel method of preparing a microtip for adhesion of an overlayer by first chemically treating the microtip.
It is still another object of the present invention to provide a novel method of preparing a microtip to bond an overlayer by depositing an adhesive layer to the microtip surface.
It is a further object of the present invention to provide a novel scanning probe microscopy microtip having selected operating properties using a paramagnetic and/or selected conductivity overlayer.
It is yet a further object of the present invention to provide a novel and improved scanning probe microscopy microtip using a final hardened overlayer to reduce microtip wear during probe use.
It is still a further object of the present invention to provide a novel microtip having an overlayer directed to provide the microtip with specific resistive and/or magnetic properties during operation with improved wear characteristics resulting from a protective overlayer.
These and many other objects and advantages of the present invention will be readily apparent to one skilled in the art to which the invention pertains from a perusal of the claims, the appended drawings, and the following detailed description of the preferred embodiments.